Combined friction and positive clutch



March 28,1939. G, T. LINDSTROM COMBINED FRICTION AND POSITIV E CLUTCH Filed Jan. 11, 1938 3 Sheets-Sheen; 1-

INVEN OR ATTORNEYS 28, 1939. G T, l |NDsTROM 2,152,552

COMBINEQF'RIG'IION AND POSITIVE CLUTCH Fil'ed Jan. 11, 1938 3 Sheets-Sheet 2 1 1k VIII/III], 1

1 WWII/#495 'IIIIIIIA March 28, 1939. (5 UNDSTROM 2,152,552

COMBINED FRICTION ANDPOSI'IIVE CLUTCH Filed Jan. 11, 1938 5 Sheets-Sheet 3 "WE/Wok.

g7 fla flwnfvg i Patented Mar. 28, 1939 PATENT OFFICE.

COMBINED FRICTION AND POSITIVE CLUTCH Gustaf Thorsten Undstrom, Tonawanda, N. Y.

Application January 11, 1938, Serial No. 184,450

3 Claims.

This invention relates to improvements in clutches-for transmitting power from one shaft to another, and particularly to clutches of this type provided with both frictional faces and 5 positively engaging parts.

One of the objects of this invention is to provide .means whereby friction clutches of stand-- 5 ard construction can be readily provided with "means for positively connecting two rotating members.

Another object is to provide mechanism of improved construction for providing a positive drivingconnection between two rotating parts after the parts have been brought to approximately the same speed by the frictional driving connection.

Anotherobiect is to provide a mechanism includlng a lever which urges the frictional parts into-engagement and which is released to permit disengagement of the frictional parts before the positively engaging parts of the clutch are moved into engaging positions.

It is also an object "of this invention to provide a friction clutch with a slidable clutch shiftstructions can, with comparatively few and minor structural changes, he made into combined friction and positive drive clutches.

Other objects of this, invention will appear from the following description and claims.

In the accompanying drawings:

Fig. 1 "is a longitudinal central sectional view of one form of combined friction and positive clutch embodying this invention.

Figs. 2, 3,. 3a, and 4 are fragmentary views, partly in section, of the clutch shown in Fig. 1 and showing the parts in successively different positions.

Fig. 5 is a transverse section thereof, on line 55, Fig. 1.

-Fig. Gisa fragmentary longitudinalcentral sectional view of a combined friction and positive clutch of modified construction.

Figs. 7 and 8 are fragmentary face views of portions thereof. 2

Fig. 9 is a corresponding face view of a slightly modified construction.

Fig. 10 is a fragmentarylongitudinal central sectional view of still another friction clutch having my invention applied thereto.

Figs. 11 and, 12 are views similar to Fig. 10,- but showing parts of the clutch in different positions.

Fig. 13 is a transverse section thereof, on line |3--l3, Fig. 10.

Fig. 14 is a section similar to Fig. 10, showing the position which the clutch parts assume in moving from the relation shown in Fig. 11 to that illustrated in Fig. 12.

Fig. 15 is a fragmentary longitudinal central sectional view of another type of friction clutch having the improvements embodying this invention applied thereto.

I have illustrated by way of example several well known types of friction clutches to which I have applied improvements embodying this invention for the purpose of combining with these friction clutches positive connections between the driving and driven members. In many instances where friction clutches are employed, for example in the textile industry, it is frequently very desirable to have a positive connection between the driving and driven members, since even slight slippage of a friction clutch will result in defects in the product. In accordance with my improvements, the friction clutches are employed only for bringing the driven member approxi mately to the speed of rotation of the driving member, whereaftier upon further movement of the clutch shipper, the pressure on the friction clutch is released and a positive connection between the driving and driven members is made. In Figs. 1 to 5, I have illustrated my invention applied to one well known type of friction clutch. In this construction, I! represents a shaft which is iournalled in bearings l6 and I1 and which may form the driven member of the clutch.-

A gear 18 having gear teeth l9 may constitute the driving member of the clutch and this memher is mounted to rotate freely upon the shaft II.

The frictional driving connection gbetween the driving and driven members is finned in the usual mannerby means of a plurality of friction disks 20, alternate disks being splined to the interiorfface of a ring-shaped member 22 bolted or otherwise secured on the driving gear 18, the

other disks being splined to the shift I! as indicated at 24. Consequently, when these disks are pressed into contact with each other, power is transmitted through the ring-shaped member from the driving gear I8 to theshaft l5, and when the pressure on the disks is released, the driven disks connected with the ring-shaped gm'em- 65 her 22 rotate with the driving gear l3 and relatively to the disks splined to the driven member or shaft l3, so that the transmission of power from the driving member to the shaft, I5 is interrupted. In this clutch, as well as in other friction clutches herein described, it will be obvious that, if desired, the driven member may be employed as the driving member, in which case the member herein described as the driving member, becomes the driven member.

In this particular type of clutch, pressure is' applied to the disks through the medium of a compression ring 25 which is mounted to rotate with and to slide lengthwise of a clutch hub or sleeve 21 rigidly secured on the shaft l5, for example, by means of a key 23 and pin 23a. The clutch hub is suitably positioned with reference to the bearing 16 in any suitable manner, for example, by means of a spacer collar 29 and a stop washer 33. A sliding member or element 32 is splined to the clutch hub 21 by means of a spline 33 and this sliding element may be actuated in any suitable or desired manner, for example, by means of shifter studs 33 extending into an annular groove formed in the outer face of the sliding element and connected to a shifter lever or shipper 35, only portions of which are shown in s. 1 to 4. g v

- Pressure is applied to the pressure ring 23 of the clutch by means of a series of levers 31 pivoted at 38 on the clutch hub and having cam faces 33 by means of which the levers may be swung about their pivots 38, three levers being shown in the construction illustrated, see Fig. 5. The levers also have shoulders or cam faces 40 engaging the pressure ring '23 so that when the levers are swung from their normal positions in which they apply no pressure to the clutch, as shown in Fig. 2,.to the position shown in Fig. 3, the clutch disks will be pressed into engagement with each other to establish a driving connection between the gear l3 and the shaft l5. These levers 31 are preferably mounted in recesses 4| formed in the peripheral face of the clutch hub 21. and movement is imparted to the levers 31 by means of pins or studs 42, rigidly secured on the slidin member or element 32, one of these pins ex-- tending into each recess 4|.

The operation of this type of friction clutch will be obvious, since the movement of the sliding element 32 to the left in Figs. 1 to 4 will result in the pins 42 engaging the cam portions 39 of the levers 31 and thus causing the projections or of this invention.

In order to adapt a friction clutch of this type to provide a positive connection between the driving and driven members, I provide inter-engaging teeth or projections on parts connected with the driving and driven members. These teeth enter into engagement after the maximum pressure has been exerted on the friction disks by the levers 31.

I further provide for relieving the pressure on the friction disks so as to permit relative-movement of the teeth carrying members, so that the teeth or projections of these two members may enter stantially the speed of the driving member.

now on the market, teeth or other members for positive engagement with the driving member may be formed on the sliding element or member which is actuated by the shipper lever and which acts on the levers which move the friction disks into frictional contact. The sliding elements or members of such clutches are generally splined to sleeves which are keyed or otherwise fixed on the driven shafts and consequently, power can sliding element or member with an extension or flange 34, the outer edge of which extends near the ring-shaped extension 22 of the driving member l3. Consequently, I provide a series of teeth 45 on the ring-shaped extension 22 of the driving member, and corresponding teeth 43 on the flange 43 of the sliding element 32. These teeth may be of any suitable or desired shape and are arranged so that they become interlocked when the sliding element 32 is moved to the limit of its movement to the leftin Figs. 1 to 4, as shown in Fig. 4.

Since a correct and positive engagement of the interlocking teeth takes place only if the teethon the sliding element are in correct relation to the teeth 43 on the driving member, I provide means for releasing the pressure on the'friction disks just prior to the engagement. of the. teeth 46 with the teeth 43. I accomplish this by providing the pressure levers 31 with a recessed or relieved portion or cam "which joins'the cam face 39 of the lovers, as clearly shown in Figs. 2 to 4, the cam faces or depressions 41 being provided with inclined portions 43 which extend from the depressed portions 41 to the cam faces 33.

As a result of this construction, it will be clearly seen by reference to Figs. 2 to4, that as the sliding member 32 is moved to the left from the position shown in Fig. 2, in which the friction disks are out of driving contact, the pins or studs 42, of the sliding element first engage the cam face 39 and swing the levers l1 into the positions shown in Fig. 3 in which they press the friction disks into driving contact. This results in the frictional transmission of power from the driving member l3 to the drivenshaft I, which shaft is then accelerated until it acquiressubsoon as this has been accomplished, the shifter lever 33 is moved further to move the sliding element 32 further to'the left, whereupon the pins 42 engage the faces 43 which are inclined oppositely to the faces 33. This permits the levers 31 to move back into the positions in which pressure on the friction disks is released, and also of the sliding element to the left, the teeth .33

are moved into engagement'with the teeth 43, the pins 42 during this movement travelling along the substantially flat portion 41 at the bottom of the cam depression in each lever 31, see Fig. 4.

20, v illustrated in Figs. 1 to 5, I have provided the the element to'th'e clutch hub or sleeve :4, through If, during the driving of the shaft II through the friction disks, the teeth 88 should not be in correct relation to the teeth 85 to enter into therecesses between these teeth, then by relieving the pressure. on the friction disks, the driven member or shaft I! will tend to lag behind the driving member sumciently to permit the teeth 4G to be engaged into correct relation between the teeth 45. A positive driving connection between the driving and driven members is, consequently, .formed by these teeth. and during the period in which the positive drive connection is in operation, pressure on the friction disks is relieved. This results not only ina positive and accurate driving of the driven member at the same speed as the driving member, but also relieves the friction disks of any work or movement relatively to each other, so that the life of the frictional power transmission portion of the clutch is greatly increased.

In the construction shown in Figs. 6 to 9, a somewhat different type of friction clutch is illustrated. In this'construction, amember 5b which may be the driving member is rotatably mounted on a shaft 5| which constitutes the driven member. The driving member 58 is pro-.

vided at one side thereof with an outwardly; extending flange or hub portion 52, the inner surface of which is adapted to cooperate with an expanding band 53, 58 represents a clutch hub or sleeve arranged abqut the shaft 5| and secured thereto by one or more keys 55. This clutch hub or sleeve has the expanding band 58 connected therewith in any suitable manner, for example, by means of a pin 51, and this hub or sleeve is provided with recessed portions 58 in which expanding levers or fingers 59 are arranged.

These levers or fingers extend between and engage the ends of the expanding band 53, the

ends of the band for this purpose being provided with arc-shaped recesses 88 into which correspondingly shaped bosses or projections 5| of the levers 58 enter. The portions of the levers arranged between the ends of the expanding band 53 are in engagement with each other and the opposite ends of the levers are provided with cam faces 52. When these ends of the levers are spread apart,.as shown in Fig. 7, theband 58 will be expanded into frictional engagement with the inner surfaces of the flange 52, and thus form a driving connection between the driving member 50 and the shaft 5L.

Actuation of the levers 58 is accomplished by means of a slidabie element or member 85 secured against rotation relatively to the clutch hub or sleeve 54 by means of one or more splines 54.

The slidabie element has a pin or stud 88 extending into the recess 58 for actuating the levers 58, I

as' has been described. Allof these parts of the clutch have heretofore been known and of themselves constitute no part of this invention.

' In order to provide. for a positive connection between the driving and driven members of this clutch, Iprovide "positive inter-engaging teeth on the driving member 58 and on the sliding member 85. For example. in the construction shown in Figs. 6 to 9, I have provided the sliding member with a flange 81 on which is provided one set of teeth 88. A correspondingset of teeth 88 is provided'on the hub 52 of the driving'member 58.

Consequently, when the sliding element is moved to the limit of its movement to the right in Fig; '6,

the teeth il wili'engage between the teeth it to' form a positive driving connection from the driving member 58 to the sliding element 88, and from the spline 68, and from this clutch hub to the driven shaft through the keys 55.

In order to relieve the friction connection just prior tothe engagement of the teeth 68 and 8., I have provided recessed or depressed c'am faces 18 on the edges of the levers 59 which face each other. These cam faces are so formed that after the levers 59 have been spread apart to their maximum extent by means of the pin or stud 6B engaging the cam faces 62, this pin or stud enters into the oppositely facing depressed portions or cam faces 18 and this permits the levers 59 to move from the position shown in Fig. 7 to those shown in Fig. 8, thus permitting the expanding band 53 to return to its-normal position out of driving engagement with the inner face of the flange or hub 52. It will, consequently, be obvious that when the sliding element or member s 55 is moved to the right from the position shown is provided on its outer surface into which the usual shifter studs (not shown) may extend.

In Fig. 9, I have shown a slight modification of V the clutch described in Figs. 6 to 8, namely, that I have replaced the pin 86 by means of a camshaped member 55 carried on the inner face of the sliding element or member 65 and engaging with the cam faces of the levers 59 in the same manner as the pin 66.

In Figs. l0 to 14 inclusive is shown another type of friction clutch in which a driving member 88 is rotatably mounted on the driven shaft 8|. The

member has an annular flange or hub portion 82 within which friction disks 88 are arranged, alternate disks being splined to the inner face of the flange or hub portion 82 and the remaining disks being splined to a clutch hub or sleeve 84 suitably keyed or otherwise rigidly secured to the shaft 8| In this construction, the friction disks may be pressed toward each other by means of a compression ring 85 and a series of levers 85 each pivoted at 81 on a recessed portion of the clutch hub or sleeve 84. The pressure against these disks is resisted at the opposite side thereof by means of an annular adjustable member 88 mounted on the clutch hub or sleeve 84.- V

The friction clutch is actuated by means of a Sliding element or member having an annular.

groove SI for a clutch shipper (not shown). The

slidabie element is siidably arranged on the clutch hub or sleeve 84 in any suitable manner, preferably by means of a splined connection with suitable keys 82- (Flg. 13). Theslidable element is alsoprovided with cam flngers 9: which are rigid-- ly secured to 'the inner cylindrical surface of the sliding member 88 and engage the levers 88 for swinging the same from the inoperative position shown in Fig. 10 to an operative position shown the outer edge of which extends into proximity to 1 hub 82 of' the driving member. I also provide cooperating teeth 95 and 90 respectively on the hub 82 of the driving member 80 and on the flange 94 of the sliding element or member 90, the teeth being so arranged as to move into engagement during the final movement of the member 90 to the right in Figs. 10 to 12 and 14.

I also recess or undercut the arms of the levers 86 which are engaged by the cam fingers, to form cam or pressure relieving faces 9'1 thereon. I

also provide notched or cam faces 98 on the leverengaging sides of the cam fingers 93 which act in such a manner that if the sliding element or member 90 is moved to the right beyond the position shown in Fig. 14, the relieved or cam portions 91 and 98 will cooperate to permit the levers 86 to swing back from their maximum pressure applying positions shown in Fig. 14, and thus relieve the friction disks and permit slipping or relative movement of the driving and driven members of the clutch which allows the proper meshing of the teeth 95 and 96.

In Fig. 15 is illustrated another form of friction clutch to which I have applied my improvements. In this type of clutch, the shaft I may be the driving member and the shaft IN the driven member. The shaft I00 has keyed thereto a clutch housing or enlarged hub I02 on which alternate clutch disks I03 are secured The remaining clutch disks are connected with or splined to a clutch sleeve or hub I 04. This sleeve or hub also carries a pressure applying ring or member 105 which is actuated through links I 08 by ,means of levers I01, only one link and. one lever being shown in Fig. 15. The slidablefclutch actuating member or element in this case is the part I08 which also has a 'cam face I09 adapted'to engage an end of each lever I0'I, this sliding member being slidably mounted on the driven shaft MI by means of a spline IIO.

Since in this type of friction clutch, the hub or sleeve part of the slidable member I08 does not extend into proximity to the driven member, I

. have provided the slidable member I08 with an the teeth-on the flange II3 will engage with the teeth of the housing part I02 to form a positive driving connection from the driving shaft IN and the housing part I02. slidable member, also cooperates with the housing part I02 to form a housing enclosing the friction clutch. I

In order to disengage the friction disks when the teeth H4 move into engagement, I provide on the inner face of the sliding member I08 arecess or depression 5, and I also relieve or indent the portion IIG of the inner faces of the levers I 01 so that the ends of the levers I01 may enter-into the recess or depression H5 and thus permit the levers to swing into positions to relieve pressure on the friction disks.

It will be obvious that in the operation of this clutch by movement of the sliding member or element- I08 from released or disengaged portion toward the driving member, the levers I01 will first be swung by the cam members I09 into This extension of the positions to apply the maximum pressure to the friction disks, and upon further movementof the sliding element I08 in the same direction, the ends of the levers 101 will enter the depression H5, so that pressure on the friction members is relieved. The teeth Ill can thenbe readily converted into combined friction and positive I clutches. This can be done with very little change in the construction of the slidable member, and by relieving the usual pressure levers, and in some cases also the cams or parts actuating them, in such a manner that the frictional transmission of power is interrupted just prior to engagement of the positive driving members or teeth. By means of my improvements, I not only produce clutches which can be absolutely relied upon to transmit power positively and Without slippage from the driving member, but

also I greatly increase the life of the clutches by rendering the frictional drives inoperative except during starting.

It will also be noted that in all of the forms of my invention shown, the extension of the slideable member extends about portions of the friction clutch mechanisms, and when the clutches are in engaged positions, they are 811- tirely enclosed so that the clutch mechanisms are protected from damage from the exteriors thereof. 7

I claim as my invention:

1. A combined friction and positive drive clutch having the combination with a driving rotary member and a driven rotary member, a plurality of cooperating clutch disks on said members movable into and out of frictional engagement, a sleeve fixed on one of said members, and a collar slidable on'and rotatable with said sleeve, of sets of circumferential opposed teeth on one of said members and on said collar respectively, which are normally disengaged and which, upon travel of said collar to a predetermined position in one direction, engage to form a positive drive connection between said rotary members, a lever pivoted on said sleeve, a camface on said lever, a pin on said collar which, as said collar travels toward tooth engaging position,-engages said cam and swings said lever to a position in which it press'es said friction disks together and effects frictional drive connection between said two rotary members, said lever'having a second cam face opposed to said other cam face, which, as said-pin leaves said first cam face in' the continued travel of said collar, engages said pin and permits said lever to swing in an opposite direction by action of said friction disks as a result of their tendency to separate when relieved of said pressure, thus de-clutching said driving .and driven members from frictional drive while they continue to rotate at substantially the same speed, and whereupon;.by the continued move- 'ment of-said collar its travel-in said beforementioned direction will be completed and said sets of teeth will engage to eflect positive drive connection between said driving and driven members while said friction drive connection remains inoperative.

2. Acombined irictionandpodtive drive clutch havinz the combination with a rotary I member and a driven rotary member, a phirality or clutch disks on said members movable into out or engage ment, a sleeve: fixed on one of members, and a collar slidable on rotatable with sleeve, oi sets of circumferential opposed on one of said members and on said collar respectively which are normally ed and which, upon travel of said collar to a.v predeterposition in. one engage to form 1| a. positive drive connection between said rotary members, a plurality of levers pivoted on said sleeve in equally spaced relation and each a movable into a position to pras said friction disks together and I. eilect frictional drive connection between said two rotary members, a cam face on each lever, a set of symmetrically pins fixedv on said collar adjacent said levers and mir or which, upon movement of said collar towards 2; said position, engages: the cam of an adjacent lever and. swings that: lever position for applying the aforesaid pressure to said friction disks, each oi said levers having av relief recess into which the adiacent pin is received after said pin has passed over cam of that lever and whereby said levers are in an opposite direction. by action of said friction disks as a. result of their tendency to separate when relieved of pressure, thus de-clutching said driving and driven members, teeth on one member and on. said. collar being then engageable by continued movement of said collar iriv the same direction and while said irictiorr drive is inoperative, and. means for eifecting predetermined travel of said collar and iull engagement of said setsof teeth, and said pinsbeing arranged in definite relationship to said lever cams and to said driving and driven members so that the positive engagement of said members is tmailected by wear between said friction disks. 3. A combined friction and positive drive clutch ior use-at high speeds having the combination with a driving rotary member and a driven rotary member disposed? in axial aiinement and each being of form with relation to: its a plurality oi clutch disks on said members in symmetrical relation totheiraxesandwhiclraremovableintoand 5 out of engagement, a concentric sleeve fixed on one or and a concentric collar slidable on and rotatable with said sleeve,

whicharenormall'y I "ltld'hichm travelotsaidcollartoapodtion in one engage to form a positive drive said rotarymembers,apluralitv of equally radially disposed pivots on said sleeve, a w- H number of levers mounted on pivots: in dynamicallybalancedrelatiom to theaxisofsaidclutch to swing tangentially to the circumference of said sleeve and each a movable into Q a to press said iriction'dflka together to eflect frictional drige connection between said two rotary members, a can face on each lever,

av set of symmetrically pins fixed on said collar adjacent said levers of which, 5 upon movement of toward tooth engagingposition, engages a! cam of an adjacent lever and swings said lever into position for applying the aioresaid pressure to said iricflon disks, eachofsaidleversamhavingasecond cam terminating inv a relief recess, W that, after the respective pins have passed over said first cams in the travel of said collar, said levers are: caused to engage the seccams with said pins and swing to pressure I relieving position with respect to said friction and said pins thenceforth moving in said lever recesses during the completion of the collar to positive tooth engaging position, whereby positive drive engagement of said clutch members is 4 effected whilefriction drive connectim is inoperative, and said members, said sleeve, said collar, said pins and said levers being symmetricalls disposed in dynamic balance with respect totheclutchaxissothatsaidclutch mavrun at higlispeedswithout detrimenttoits operation by centrifugal influence.

(were! n MOI. 

